Abstract: It is generally recognized that time-stress superposition principle (TSSP) can effectively simplify the constitutive models and mechanical performance tests of viscoelastic polymers. Previous studies mainly focused on the uniaxial stress state, while practical engineering components are usually under biaxial or triaxial complex stress state. To this end, we first utilized the finite element method to reasonably design and optimize the biaxial cruciform specimens, so as to made the stress and strain in the test area of the sample basically satisfy uniform distribution, and processed the silicone rubber samples accordingly. Secondly, we carried out biaxial creep tests on the samples under various stress levels and diverse load ratios, a series of short-term creep test curves were acquired. Finally, we defined appropriate stress and deformation measures based on Cauchy stress and Left Cauchy-Green deformation tensor to investigate TSSP under biaxial tension. According to the shift method, we shifted the short-term creep curves under diverse load levels along the logarithmic time axis to construct the master curve in a wide time domain, and obtained the corresponding shift factors as well. Furthermore, nonlinear regression analysis of the shift result was conducted by using the stress shift factor equation, and the corresponding equation parameters were obtained. Consequently, the research results can provide theoretical basis and important reference for accelerated characterization of long-term mechanical properties and long-term life prediction of viscoelastic polymers under complex stress conditions.
Williams M L, Landel R F, Ferry J D. Journal of the American Chemical Society, 1955, 77(14),3701.2 O′Shaughnessy M T. Textile Researc Journal, 1948, 18(5),263.3 Schapery R A. Mechanics of Time-Dependent Materials, 1997, 1(2),209.4 Knauss W G, Emri I. Polymer Engineering & Science, 2010, 27(1),86.5 Jin R, Liu W. Journal of Beijing Institute of Chemical Technology(Natural Science Edition), 1994(1),35(in Chinese).金日光, 刘薇. 北京化工大学学报(自然科学版), 1994(1),35.6 Brostow W. Materials Research Innovations, 2000, 3(6),347.7 Luo W, Wang C, Hu X, et al. Acta Mechanica Solida Sinica, 2012, 25(6),571.8 Kim G H, Lu H, Kim G H, et al. Polymer Testing, 2008, 27(1), 114.9 Zhang J, Xiong Y, Guo S Y, et al. Polymer Materials Science and Engineering, 2015(11), 56 (in Chinese).张建伟,熊英,郭少云,等. 高分子材料科学与工程. 2015(11),56.10 Zhang J, Jiang H, Jiang C, et al. Polymer Testing, 2015, 44, 8.11 Ahmed J. Time-temperature superposition principle and its application to biopolymer and food rheology, Woodhead Publishing, Britain, 2017.12 Ulven C A, Hosseini N, Amiri A. Journal of Renewable Materials, 2015, 3(3),224.13 Carniel E L, Hrelja D, Zulian D, et al. Journal of Materials Design & Applications, 2016, 230(2),674.14 Tanks J, Rader K, Sharp S, et al. Composit-E Structures, 2017, 159,455.15 Cai D,Zhou G,Wang X, et al. Journal of Materials Engineering, 2014(5),73(in Chinese).蔡登安, 周光明, 王新峰,等. 材料工程, 2014(5),73.16 Wang Y, Fang D. Acta Mechanica Sinica, 2002, 34(5),705(in Chinese).王颖晖, 方岱宁. 力学学报, 2002, 34(5),705.17 Yang T. Viscoelastic theory and application.Science Press,China, 2004(in Chinese).杨挺青. 黏弹性理论与应用. 科学出版社, 2004.18 Hariharaputhiran H, Saravanan U. Mechanics of Materials, 2016, 92,211.
渝公网安备50019002502923号 版权所有：《材料导报》编辑部
2019, Vol. 33 
